Windows That Double as Solar Panels Are in the Works

The cost and efficiency of solar panels continue to decline as companies and policymakers hope that abundant energy from the sun could help replace power generated by burning fossil fuels. As such, solar panels are becoming increasingly common not just in large solar energy installations, but on commercial and residential rooftops as well. Researchers at the University of Michigan, however, hope that newly developed technology could one-day harvest energy from building exteriors beyond just the roof. Current silicon-based solar panels are decidedly not see-through, but so-called organic solar cells, made from a plastic material, can be largely transparent — making for a tantalizing prospect for energy-harvesting windows. They haven’t become practical on a large scale, however, due to low efficiency, short lifespans, and other engineering challenges. Michigan electrical engineering professor Stephen Forrest’s lab was able to create organic cells that could last up to 30 years at efficiencies of 10% — less than its silicon-based counterparts, but enough to potentially be a viable solar window.